Hidden zeros for particle/string amplitudes and the unity of colored scalars, pions and gluons

TL;DR

This paper reveals that string-inspired scalar amplitudes secretly encode pion and gluon scattering amplitudes, sharing hidden zeros and factorization properties, unifying these theories through a simple kinematic shift at tree level.

Contribution

It uncovers the hidden zeros and factorization properties in Tr(φ^3) amplitudes and demonstrates their unification with pion and gluon amplitudes via a kinematic shift.

Findings

Amplitudes vanish at specific non-planar Mandelstam invariants.

Near zeros, amplitudes factor into smaller amplitudes.

Unified description of scalars, pions, and gluons through a kinematic shift.

Abstract

Recent years have seen the emergence of a new understanding of scattering amplitudes in the simplest theory of colored scalar particles - the Tr$(\phi^3)$ theory - based on combinatorial and geometric ideas in the kinematic space of scattering data. In this paper we report a surprise: far from the toy model it appears to be, the ''stringy'' Tr$(\phi^3)$ amplitudes secretly contain the scattering amplitudes for pions, as well as non-supersymmetric gluons, in any number of dimensions. The amplitudes for the different theories are given by one and the same function, related by a simple shift of the kinematics. This discovery was spurred by another fundamental observation: the tree-level Tr$(\phi^3)$ field theory amplitudes have a hidden pattern of zeros when a special set of non-planar Mandelstam invariants is set to zero. Furthermore, near these zeros, the amplitudes simplify, by factoring into a non-trivial product of smaller amplitudes. Remarkably the amplitudes for pions and gluons are observed to also vanish in the same kinematical locus. These properties further generalize to the ''stringy'' Tr$(\phi^3)$ amplitudes. There is a unique shift of the kinematic data that preserves the zeros, and this shift is precisely the one that unifies colored scalars, pions, and gluons into a single object. We will focus in this paper on explaining the hidden zeros and factorization properties and the connection between all the colored theories, working for simplicity at tree-level. Subsequent works will describe this new formulation for the Non-linear Sigma Model and non-supersymmetric Yang-Mills theory, at all loop orders.